A blog about Exalogic, Coherence, ADF, JDeveloper and other Oracle Technologies

The "initialization error: class file has wrong version" has become a somewhat recurrent error message thrown by JDeveloper 10.1.2.x as newer JDKs have been released in the last years. Note that JDeveloper 10.1.2 was developed to run with JDK 1.4.2.

The reasons for this error message to be thrown include:

A JDK version higher than 1.4.2 is being used and some unexpected incompatibility conflicts can occur because of that

Some of the libraries used on the workspace and/or project were compiled with a newer JDK version

So, it is strongly recommended to use newer JDeveloper versions (10.1.3 - 11g) for newer JDKs.